<html>
    <head>
        <meta charset="utf-8">
        <title>www.husonghe.com</title>
        <style>
            html {
                height: 100%;
                background-image: -webkit-radial-gradient(ellipse farthest-corner at center center, #1b44e4 0%, #020f3a 100%);
                background-image: radial-gradient(ellipse farthest-corner at center center, #1b44e4 0%, #020f3a 100%);
                cursor: move;
            }

            body {
                width: 100%;
                margin: 0;
                overflow: hidden;
            }
        </style>
    </head>

    <body>


        <canvas id="canv" width="1920" height="572"></canvas>
        <script>
            var num = 200;
            var w = window.innerWidth;
            var h = window.innerHeight;
            var max = 100;
            var _x = 0;
            var _y = 0;
            var _z = 150;
            var dtr = function (d) {
                return d * Math.PI / 180;
            };

            var rnd = function () {
                return Math.sin(Math.floor(Math.random() * 360) * Math.PI / 180);
            };
            var dist = function (p1, p2, p3) {
                return Math.sqrt(Math.pow(p2.x - p1.x, 2) + Math.pow(p2.y - p1.y, 2) + Math.pow(p2.z - p1.z, 2));
            };

            var cam = {
                obj: {
                    x: _x,
                    y: _y,
                    z: _z
                },
                dest: {
                    x: 0,
                    y: 0,
                    z: 1
                },
                dist: {
                    x: 0,
                    y: 0,
                    z: 200
                },
                ang: {
                    cplane: 0,
                    splane: 0,
                    ctheta: 0,
                    stheta: 0
                },
                zoom: 1,
                disp: {
                    x: w / 2,
                    y: h / 2,
                    z: 0
                },
                upd: function () {
                    cam.dist.x = cam.dest.x - cam.obj.x;
                    cam.dist.y = cam.dest.y - cam.obj.y;
                    cam.dist.z = cam.dest.z - cam.obj.z;
                    cam.ang.cplane = - cam.dist.z / Math.sqrt(cam.dist.x * cam.dist.x + cam.dist.z * cam.dist.z);
                    cam.ang.splane = cam.dist.x / Math.sqrt(cam.dist.x * cam.dist.x + cam.dist.z * cam.dist.z);
                    cam.ang.ctheta = Math.sqrt(cam.dist.x * cam.dist.x + cam.dist.z * cam.dist.z) / Math.sqrt(cam.dist.x * cam.dist.x + cam.dist.y * cam.dist.y + cam.dist.z * cam.dist.z);
                    cam.ang.stheta = - cam.dist.y / Math.sqrt(cam.dist.x * cam.dist.x + cam.dist.y * cam.dist.y + cam.dist.z * cam.dist.z);
                }
            };

            var trans = {
                parts: {
                    sz: function (p, sz) {
                        return {
                            x: p.x * sz.x,
                            y: p.y * sz.y,
                            z: p.z * sz.z
                        };
                    },
                    rot: {
                        x: function (p, rot) {
                            return {
                                x: p.x,
                                y: p.y * Math.cos(dtr(rot.x)) - p.z * Math.sin(dtr(rot.x)),
                                z: p.y * Math.sin(dtr(rot.x)) + p.z * Math.cos(dtr(rot.x))
                            };
                        },
                        y: function (p, rot) {
                            return {
                                x: p.x * Math.cos(dtr(rot.y)) + p.z * Math.sin(dtr(rot.y)),
                                y: p.y,
                                z: - p.x * Math.sin(dtr(rot.y)) + p.z * Math.cos(dtr(rot.y))
                            };
                        },
                        z: function (p, rot) {
                            return {
                                x: p.x * Math.cos(dtr(rot.z)) - p.y * Math.sin(dtr(rot.z)),
                                y: p.x * Math.sin(dtr(rot.z)) + p.y * Math.cos(dtr(rot.z)),
                                z: p.z
                            };
                        }
                    },
                    pos: function (p, pos) {
                        return {
                            x: p.x + pos.x,
                            y: p.y + pos.y,
                            z: p.z + pos.z
                        };
                    }
                },
                pov: {
                    plane: function (p) {
                        return {
                            x: p.x * cam.ang.cplane + p.z * cam.ang.splane,
                            y: p.y,
                            z: p.x * - cam.ang.splane + p.z * cam.ang.cplane
                        };
                    },
                    theta: function (p) {
                        return {
                            x: p.x,
                            y: p.y * cam.ang.ctheta - p.z * cam.ang.stheta,
                            z: p.y * cam.ang.stheta + p.z * cam.ang.ctheta
                        };
                    },
                    set: function (p) {
                        return {
                            x: p.x - cam.obj.x,
                            y: p.y - cam.obj.y,
                            z: p.z - cam.obj.z
                        };
                    }
                },
                persp: function (p) {
                    return {
                        x: p.x * cam.dist.z / p.z * cam.zoom,
                        y: p.y * cam.dist.z / p.z * cam.zoom,
                        z: p.z * cam.zoom,
                        p: cam.dist.z / p.z
                    };
                },
                disp: function (p, disp) {
                    return {
                        x: p.x + disp.x,
                        y: - p.y + disp.y,
                        z: p.z + disp.z,
                        p: p.p
                    };
                },
                steps: function (_obj_, sz, rot, pos, disp) {
                    var _args = trans.parts.sz(_obj_, sz);
                    _args = trans.parts.rot.x(_args, rot);
                    _args = trans.parts.rot.y(_args, rot);
                    _args = trans.parts.rot.z(_args, rot);
                    _args = trans.parts.pos(_args, pos);
                    _args = trans.pov.plane(_args);
                    _args = trans.pov.theta(_args);
                    _args = trans.pov.set(_args);
                    _args = trans.persp(_args);
                    _args = trans.disp(_args, disp);
                    return _args;
                }
            };

            (function () {
                "use strict";
                var threeD = function (param) {
                    this.transIn = {};
                    this.transOut = {};
                    this.transIn.vtx = (param.vtx);
                    this.transIn.sz = (param.sz);
                    this.transIn.rot = (param.rot);
                    this.transIn.pos = (param.pos);
                };

                threeD.prototype.vupd = function () {
                    this.transOut = trans.steps(this.transIn.vtx, this.transIn.sz, this.transIn.rot, this.transIn.pos, cam.disp);
                };

                var Build = function () {
                    this.vel = 0.04;
                    this.lim = 360;
                    this.diff = 200;
                    this.initPos = 100;
                    this.toX = _x;
                    this.toY = _y;
                    this.go();
                };

                Build.prototype.go = function () {
                    this.canvas = document.getElementById("canv");
                    this.canvas.width = window.innerWidth;
                    this.canvas.height = window.innerHeight;
                    this.$ = canv.getContext("2d");
                    this.$.globalCompositeOperation = 'source-over';
                    this.varr = [];
                    this.dist = [];
                    this.calc = [];

                    for (var i = 0, len = num; i < len; i++) {
                        this.add();
                    }

                    this.rotObj = {
                        x: 0,
                        y: 0,
                        z: 0
                    };
                    this.objSz = {
                        x: w / 5,
                        y: h / 5,
                        z: w / 5
                    };
                };

                Build.prototype.add = function () {
                    this.varr.push(new threeD({
                        vtx: {
                            x: rnd(),
                            y: rnd(),
                            z: rnd()
                        },
                        sz: {
                            x: 0,
                            y: 0,
                            z: 0
                        },
                        rot: {
                            x: 20,
                            y: -20,
                            z: 0
                        },
                        pos: {
                            x: this.diff * Math.sin(360 * Math.random() * Math.PI / 180),
                            y: this.diff * Math.sin(360 * Math.random() * Math.PI / 180),
                            z: this.diff * Math.sin(360 * Math.random() * Math.PI / 180)
                        }
                    }));
                    this.calc.push({
                        x: 360 * Math.random(),
                        y: 360 * Math.random(),
                        z: 360 * Math.random()
                    });
                };

                Build.prototype.upd = function () {
                    cam.obj.x += (this.toX - cam.obj.x) * 0.05;
                    cam.obj.y += (this.toY - cam.obj.y) * 0.05;
                };

                Build.prototype.draw = function () {
                    this.$.clearRect(0, 0, this.canvas.width, this.canvas.height);
                    cam.upd();
                    this.rotObj.x += 0.1;
                    this.rotObj.y += 0.1;
                    this.rotObj.z += 0.1;

                    for (var i = 0; i < this.varr.length; i++) {
                        for (var val in this.calc[i]) {
                            if (this.calc[i].hasOwnProperty(val)) {
                                this.calc[i][val] += this.vel;
                                if (this.calc[i][val] > this.lim) 
                                    this.calc[i][val] = 0;
                                
                            }
                        }

                        this.varr[i].transIn.pos = {
                            x: this.diff * Math.cos(this.calc[i].x * Math.PI / 180),
                            y: this.diff * Math.sin(this.calc[i].y * Math.PI / 180),
                            z: this.diff * Math.sin(this.calc[i].z * Math.PI / 180)
                        };
                        this.varr[i].transIn.rot = this.rotObj;
                        this.varr[i].transIn.sz = this.objSz;
                        this.varr[i].vupd();
                        if (this.varr[i].transOut.p < 0) 
                            continue;
                        
                        var g = this.$.createRadialGradient(this.varr[i].transOut.x, this.varr[i].transOut.y, this.varr[i].transOut.p, this.varr[i].transOut.x, this.varr[i].transOut.y, this.varr[i].transOut.p * 2);
                        this.$.globalCompositeOperation = 'lighter';
                        g.addColorStop(0, 'hsla(255, 255%, 255%, 1)');
                        g.addColorStop(.5, 'hsla(' + (
                            i + 2
                        ) + ',85%, 40%,1)');
                        g.addColorStop(1, 'hsla(' + (
                        i) + ',85%, 40%,.5)');
                        this.$.fillStyle = g;
                        this.$.beginPath();
                        this.$.arc(this.varr[i].transOut.x, this.varr[i].transOut.y, this.varr[i].transOut.p * 2, 0, Math.PI * 2, false);
                        this.$.fill();
                        this.$.closePath();
                    }
                };
                Build.prototype.anim = function () {
                    window.requestAnimationFrame = (function () {
                        return window.requestAnimationFrame || function (callback, element) {
                            window.setTimeout(callback, 1000 / 60);
                        };
                    })();
                    var anim = function () {
                        this.upd();
                        this.draw();
                        window.requestAnimationFrame(anim);

                    }.bind(this);
                    window.requestAnimationFrame(anim);
                };

                Build.prototype.run = function () {
                    this.anim();

                    window.addEventListener('mousemove', function (e) {
                        this.toX = (e.clientX - this.canvas.width / 2) * -0.8;
                        this.toY = (e.clientY - this.canvas.height / 2) * 0.8;
                    }.bind(this));
                    window.addEventListener('touchmove', function (e) {
                        e.preventDefault();
                        this.toX = (e.touches[0].clientX - this.canvas.width / 2) * -0.8;
                        this.toY = (e.touches[0].clientY - this.canvas.height / 2) * 0.8;
                    }.bind(this));
                    window.addEventListener('mousedown', function (e) {
                        for (var i = 0; i < 100; i++) {
                            this.add();
                        }
                    }.bind(this));
                    window.addEventListener('touchstart', function (e) {
                        e.preventDefault();
                        for (var i = 0; i < 100; i++) {
                            this.add();
                        }
                    }.bind(this));
                    // window.addEventListener('resize', function () {
                    //     canvas.width = w = window.innerWidth;
                    //     canvas.height = h = window.innerHeight;
                    // }, false);
                };
                var app = new Build();
                app.run();
            })();
        </script>
    </body>
</html>
